Chalk pastel on black paper.

Looking back on this picture now, I'm not sure it fulfills the concentration very well. The dark half could just be a background. The viewer's eye is drawn to the action on the left and the Statue-of-Liberty-ish figure in the middle.

Maybe the figure should have been facing towards the darkness, instead of away from it. Or maybe something more subtle – like ze could be walking away in one direction, but turning to look back in the other.